BANNING (CBS) — Authorities are offering a $25,000 reward for information that helps solve a triple murder, in which a toddler was bound and gagged and left in a closet after his parents and another woman were slain, a police sergeant said Monday.

A family friend found the child’s 42-year-old father, Demetrius Earl Hunt, and 33-year-old mother, Natasha Biggers, along with the body of 57-year-old Cynthia Smith. They were found in a house in the 100 block of Phillips Street on September 6 of last year.

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All three died of asphyxiation, according to Banning police Sgt. Alex Diaz, who said detectives have not established a motive.

Hunt and Biggers were Banning residents; Smith’s city of residence was unclear.

Diaz said the Banning City Council approved the $25,000 reward for information on the victims’ deaths a few weeks ago.

Police said the toddler was found — his hands bound with tape and his mouth covered — after an officer outside the house heard the child whimpering.

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He was taken to San Gorgonio Memorial Hospital, where he was found to be dehydrated but otherwise unhurt.

Purvis Hunt said his son was found dead next to his girlfriend and a friend.

“It was a dope gang,” he said in remarks reported by the Riverside Press-Enterprise. Police did not confirm that drugs played a role in the slayings.

Anyone with information about the killings was asked to contact investigators at (951) 849-1194.

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